Security at the Mumbai [Images] airport has been tightened following intelligence inputs suggesting that terrorists were planning to carry out a hijacking attempt for securing the release of some terrorists.

An alert has been issued following a meeting of senior officials of Civil Aviation Ministry, Bureau of Civil Aviation Security and Home Ministry, Civil Aviation Ministry sources said on Thursday.

During the meeting, preparedness of 'different layers' of the security and safety mechanism at airports as well as in the airspace were assessed in the wake of these inputs, the sources said.

Authorities had received specific information that terrorists were planning to attack airports at Mumbai and other smaller airports like Gorakhpur and Bagdogra, they said.

Major airports across the country, especially those in the western region, have been on high alert and extra vigil for the past few weeks following the terror strikes in Mumbai.

Extra surveillance has been mounted at the airports, with additional CISF and police personnel being deployed to keep an eye in and around the terminals.

Sniffer dogs have been deployed in some airports, while plainclothesmen were also put on the job. Sky Marshals were keeping a vigil on sensitive routes, they said.